EPA Mercury Rule Based on Silly Science

February 16, 2015

The Supreme Court is set to review the Environmental Protection Agency's rules regulating power plant mercury emissions this year, and Pat Michaels, director of the Center for the Study of Science at Cato, says the agency will have to defend its decision to regulate mercury under the 1990 amendments to the Clean Air Act.

There is more mercury emitted into the atmosphere from natural sources such as volcanoes than from human activity.

Mercury, whatever its source, often sits in the air until large rainstorms come along. According to Michaels, the mercury that falls in the United States is often from China.

Just 2 percent of global emissions mercury come from the United States.

Moreover, just 0.5 percent of all mercury emissions come from American power plants.

In addition to the fact that mercury constitutes a tiny portion of the atmosphere, the EPA is tackling a problem based on misleading data. In fact, part of its justification for the rule was based on the effect that mercury would have on children born to an entirely hypothetical population: 240,000 women of child-bearing age who consume 300 pounds of freshwater fish that they or their families have personally caught each year. NCPA Senior Research Fellow Ann Purvis discussed this fact in a report on environmental litigation, noting that the EPA never actually identified a member of this population -- it merely assumed that such women existed.

To determine the harm that mercury would have upon these children, the EPA utilized a computer model which predicted that the mercury would lower the I.Q. of the children by a miniscule 0.00209 points. On top of that, says Michaels, the EPA claims the loss of 0.00209 I.Q. points will cost those children up to $6,000,000 a year due to reduced earnings.

This is the science on which the EPA's mercury regulations are based -- regulations which threaten to shut down coal plants across the country.